Re: shampoo

Kragen Sitaker (kragen@pobox.com)
Fri, 27 Aug 1999 16:05:22 -0400 (EDT)

Dave Long writes:
> In an attempt to determine a price/stuff ratio, I picked up a 7.5
> pound jar of sodium lauryl sulfate (CAS #151-21-3) solution. It's a
> Proctor & Gamble product, bought retail, so a comparison to shampoo
> ought to determine how much one pays for the active contents versus
> how much one pays for faux-alpine scenery on the packaging.
>
> What I need is a simple way to determine the concentration ratios of
> this jar and a bottle of consumer shampoo. Simple physical properties
> that can be determined in a household kitchen would be best, but if
> worst comes to worst, I suppose I could trundle out to the UC and
> see if I can weasel something.

At one time I worked at a bubblebath factory, for a week. Among other
things, I mixed the bubblebath; we typically used about half a ton of
Calblend (a mix of detergents including sodium lauryl sulfate and some
others) along with about four tons of water per batch, and about half a
dozen other ingredients in minuscule amounts.

Some things that won't work:
- density. Mixing water with stuff that dissolves in water typically
produces something with less total volum e than the unmixed
substances.
- viscosity. The viscosity depends sensitively and nonmonotonically on
concentratiosn of several othe rsubstances, such as salt.
- lather. Other substances presen t in much smaller quantities can
also produce significant lather.

Good luck.

-- 
<kragen@pobox.com>       Kragen Sitaker     <http://www.pobox.com/~kragen/>
Tue Aug 24 1999
76 days until the Internet stock bubble bursts on Monday, 1999-11-08.
<URL:http://www.pobox.com/~kragen/bubble.html>